The steering system utilized in many modern cars is a rack and pinion steering system. The rack and pinion is comprised of multiple components including the universal joints, main and intermediate shafts, and at the center is the steering rack or gearbox. It's this central unit that receives input from the driver, by way of the steering wheel and steering column and sends a mechanical signal to tie rods and steering shafts to complete smooth and efficient left and right turns. However, from time to time, the steering rack or gearbox will wear out. Quick and efficient service to repair this important component can mean the difference between a minor inconvenience and a major mechanical overhaul.
The steering rack is essentially the heart of the steering system. When it wears out or breaks entirely the ability to steer your vehicle is compromised. If this happens while you are driving, it can be extremely dangerous. It's for these reasons (and many more) that being alert to the warning signs of a bad or failing steering rack or gearbox can save you money, time and reduce the potential of an crash.
Here are a few symptoms or warning signs that alert you to a potential problem brewing with your steering rack.
1. Very tight steering wheel
Today's rack and pinion steering systems are supported by a power steering unit that utilizes hydraulic pressure to allow easy and quick steering wheel handling. When the steering wheel feels tight or is harder to turn than usual, it's typically due to the steering rack or gearbox building up more heat or a loss of hydraulic pressure from the power steering unit. Either way, it's a problem that won't go away and should be inspected as soon as possible by an ASE certified mechanic. Sometimes it's as simple as adding more power steering fluid or a minor adjustment that can solve this problem and extend the lifespan of your steering rack.
2. Leaking power steering fluid
As noted above, sometimes tight steering is indicated by low power steering fluid. However, since the steering box is hydraulically powered, the fluid levels won't decrease unless there is a leak somewhere in the system. Once you start to leak power steering fluid it means there is a loose fitting, broken gasket, or other mechanical issue causing the leak that must be fixed as soon as possible. Failure to do so will cause the steering rack or gearbox to develop excess heat, potentially breaking gears and other components that could lead to a crash.
Leaking steering fluid can be distinguished from other fluids by its smell (typically a burning oil smell). It's also typically red or pink in color and will be dripping from the back part of your motor. If you discover this type of fluid under your car, contact a mechanic as soon as possible to inspect the leak and repair it before the leak causes additional damage.
3. Grinding noise when steering
A bad or failing gearbox is typically caused by lack of proper lubrication and service. The excess heat causes metal-on-metal contact and thus creates a loud grinding noise when you turn left or right. You can really notice this sound if you are turning and hit a bump at the same time, like when you drive into a driveway. If you notice this grinding sound when you steer left or right, contact a mechanic so they can quickly diagnose and replace the steering gearbox if needed.
4. Burning oil smell
A less common warning sign of a damaged steering rack or gearbox is the smell of burning oil. Since power steering fluid itself smells like burnt oil, the strong aroma of burnt oil will be present when the steering gearbox is hot. If this occurs, stop your vehicle immediately, find a safe place to park your vehicle and call a mechanic as soon as possible. Continued driving when a steering gearbox is overheating may result in fire and catastrophic damage.
The steering rack or gearbox is an essential component vital to the smooth steering operation of any vehicle utilizing a rack and pinion steering system. If you notice any of the above symptoms or warning signs, contact a local ASE certified mechanic as quickly as possible so they can diagnose and repair any damage done.
This article originally appeared on YourMechanic.com as Symptoms of a Bad or Failing Steering Rack/Gearbox and was authored by Timothy Charlet.